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991.
The Okavango Delta in Botswana hosts abundant wildlife and a human population with diverse livelihoods. Representing a heterogeneous landscape nuanced by spatial and temporal variability, the region has recently seen an expansion of floodwaters with social impacts ranging from livelihood disruption to human displacement. This article reports on in-depth interviews conducted in 2012 regarding these transitions in Mababe, a community in the eastern Okavango Delta, to evaluate how dynamic environmental processes alter perceptions and livelihood responses. We focus on community members’ variable interactions with wildlife in spaces of human–wildlife overlap also experiencing change. While human–wildlife interactions can have negative effects, we find that perpetuating the common narrative of human–wildlife conflict overlooks how disruptions can usher in new relationships between people and animals. In order to move beyond the conflict narrative, we conclude that spatial and temporal context is essential to evaluate effects of dynamic, uneven, and sometimes unpredictable human–wildlife encounters. 相似文献
992.
Merrill Baker-Médard 《社会与自然资源》2017,30(6):723-737
Drawing on ethnographic case studies from Madagascar, this research shows that multiple marine conservation projects have institutionalized inequitable access to marine recourses along gendered lines. Despite discursive and institutional shifts toward more “collaborative” and “community-based” conservation programing, there is a deficiency of women’s nominal as well as effective participation in community management organizations. This research shows that conservation organizations’ focus on proximate drivers of marine resource use, or a politics of picking the “low-hanging fruit,” over ultimate drivers such as global commodity chains, places disproportionate emphasis on marine spatial enclosures and restricting specific, and gendered, harvest methods. To address gender bias concerning access to and control over natural resources, we must go beyond the rhetoric of “community involvement” to address gendered inequalities in conservation decision making, and whose interests are served by conservation projects. 相似文献
993.
地下水资源是北京供水系统的支柱,设立地下水水源地保护区,是保护水源地最大可能免受人类活动影响、保证水质安全的重要措施。论文以北京市某典型水源地为例,在收集相关水文地质勘查、长期动态观测、水源地开采现状、规划及周边污染源调查等成果资料的基础上,建立了地下水系统水文地质概念模型,模拟出地下水流场。通过质点追踪技术,计算水源地水力捕获带范围。综合考虑水源地周边地形、地物和潜在风险污染源等因素,确定了水源地保护区的范围。结果表明,数值模拟法能客观详细地刻画实际地下水含水层的结构与水文地质条件,划分结果可靠、准确,能为地下水管理部门提供有效合理的保护依据。 相似文献
994.
RW Jabado SM Al Ghais W Hamza DP Robinson AC Henderson 《African Journal of Marine Science》2016,38(2):217-232
Landing site and market surveys of sharks landed along the Arabian Gulf coast of the United Arab Emirates were undertaken between October 2010 and September 2012 to obtain biological data from this artisanal fishery. Data were collected on the size and sex of 12 482 individuals representing 30 species. Maximum sizes of Carcharhinus sorrah, C. amblyrhynchoides and Hemipristis elongata were extended by at least 300?mm total length (TL) compared with published global maxima. The size at 50% maturity was determined for males of five species and this indicated that the males of smaller shark species (<1 000 mm maximum TL) in the fishery were largely mature. For many species, including Loxodon macrorhinus and Mustelus mosis, overall sex ratios were male-biased, indicating that sexual segregation is likely in those species. Furthermore, sex ratios for several species, such as Rhizoprionodon acutus, showed differences across seasons. Overall, the landings contained a high proportion of juveniles, causing concerns about the sustainability of this fishery. Biological parameters of a number of species differed from those recorded earlier for the region, demonstrating a need for additional local data collection to support the development of management measures. 相似文献
995.
Many researchers and policymakers from various disciplines highlight the role of urban biodiversity in delivering ecosystem services to enhance human wellbeing in a rapidly urbanising world. This suggests powerful synergies between approaches that are often disciplinarily separated, aiming either at human wellbeing or biodiversity conservation. Strategies towards liveable and biodiverse cities would gain support from insights into the people-biodiversity interface in cities. Yet, the question of which scale of biodiversity (from ecosystems to genes) benefits urban people in general and different socio-cultural groups in particular, remains largely open. To assess the current scientific knowledge as well as potential for further research, we systematically reviewed literature on people’s perception and valuation of urban biodiversity (200 studies). We also quantified the outcomes of studies in terms of the effects of biodiversity on valuation for studies that addressed biodiversity valuation below the ecosystem scale. We found that the current literature is critically biased in four ways. (1) Most studies cover temperate climates, while regions with the most pronounced urban growth are underrepresented. (2) Studies focus on urban forests and parks while important informal greenspaces are largely neglected. (3) Biodiversity is mostly addressed at the ecosystem scale (habitat or land-use types) while diversity at the species community or gene scale—key issues in biodiversity conservation—is covered to a much lesser extent. Most studies below the ecosystem scale show positive biodiversity effects, but universal patterns are not apparent due to the scarcity and low comparability of research. (4) Almost no studies consider the cultural diversity of urban residents by systematically targeting people from different socio-economic and cultural backgrounds or specific age groups. Our review reveals critical knowledge gaps about the people-biodiversity interface in cities, both in approaching cultural and biological diversity (‘biocultural diversity’). This shows unexploited opportunities and future directions in linking usually separated strategies on enhancing human wellbeing and biodiversity conservation in sustainable cities. 相似文献
996.
997.
Maya Pasgaard Tania Fredborg Nielsen 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2016,116(2):134-146
Explicit notions of “communities”, as key actors in conservation and development projects across the Global South, are common. Narratives about “indigenous people” or “forest-dependent communities” in forest conservation programmes prevail, portraying a picture of “communities” as homogeneous and harmonious entities. In this study, we unfold “communities” as a construct with an empirical example of a community-based forest protection project, Northern Cambodia. Based on qualitative interviews, field observations and document analysis, we examine the “community” construct in terms of establishment of boundaries, geographical composition and social coherence. We not only find that the establishment of forest “community” boundaries are dominated by powerful external actors rather than the “community members” themselves, but that the spatial composition of “communities” is complex, and affects the ability of local people to benefit from the project. We also find that the studied “communities” show low levels of social coherence and mainly consist of migrant farmers, as opposed to common policy narratives. Taking these inconsistencies into account, we discuss implications of constructing “communities” for the success of forest conservation projects, and argue in favour of more discursive and political analyses to better understand, acknowledge and adapt to existing and changing conditions in present and prospective project locations. 相似文献
998.
Social capital has the potential to influence the success of biodiverse carbon plantings in the face of uncertainty amongst rural landholders about the need or efficacy of efforts to address climate change through tree planting. We conducted 17 face-to-face semi-structured interviews with landholders in Victoria, Australia who voluntarily participate in biodiverse carbon plantings on their land, focusing in particular on the role of social capital for understanding how ‘early adopters' can advocate for programs locally. The interviews revealed the importance of social networks and the profound impact of trusted peers on the diffusion of carbon planting schemes. These social capital dimensions are especially important for shaping ongoing participation and the ways in which participants become active agents in trusted relationships that influence the participation of others. Our results suggest that the positive impact of social networks can counteract doubts about the validity of climate adaptation responses such as carbon planting, and enable landholders to connect the program with their existing stewardship motivations. The ability for early adopters of the program to demonstrate the physical materialisation of their plantings to others was vital to this process. We propose that targeting champions and trusted peers in local communities could accelerate the proliferation of biodiverse carbon planting schemes. 相似文献
999.
Soil erosion is one of the major causes of land degradation in arid areas. Soil erosion models, e.g. the revised universal soil loss equation (RUSLE), use arithmetical expressions to explore relationships among various processes occurring in the terrain. The established model includes soil parameters, slope, climate and human activities to estimate the water erosion rate and sediment yield. In this study, an approach was adopted to integrate RUSLE model and geographic information system to detect erosion vulnerability and determine the soil erosion risk in the study area. The study area is situated in the Eastern Desert, Egypt. Ground truth data were examined to represent two regions: Luxor-Suhag and Suhag–ElMinya. These regions are exampled by four dry valleys named Sannor, Tarfa, Asyut and Qena, which are planned for agricultural development. The results indicate high risk of water erosion and sediment load discharge into the cultivated land in Luxor–Suhag region. The other region of Suhag–ElMinya is moderately affected by water and sediment load discharge. A higher soil erosion rate was found in Qena wadi followed by Asyut, then Tarfa and Sannur, respectively. 相似文献
1000.
《Marine Policy》2016
One of the main challenges of international environmental agreements is improving relevant policy actions to promote adequate environmental responses. To support the work of decision makers, recent studies have used environmental and social indicators to construct global and regional-scale indices. This study aimed to use the Ocean Health Index and the Management Ranking for Brazilian States to assess Brazil’s performance regarding the Aichi Biodiversity Targets (ABTs) for coastal and marine ecosystems. Thus, six ABTs were matched and their performance was evaluated. These ABTs focused on the following topics: pollution, fish and invertebrate stocks, pressures on coral, threatened species and their conservation, the contribution of biodiversity to carbon stocks and the national biodiversity strategy and action plan. However, although the indices used showed many pathways to explore how Brazil is performing, it is still complex to evaluate ABTs’ performance regarding coastal and marine ecosystems at a global and regional scale. 相似文献